I'm also somewhat out of the loop. What I do know:
AMD Ryzen CPUs seem to be the way to go for bang-for-buck right now.
Nvidia 10-series GPUs are great. 20-series are not enough better to justify the price. Depending on what you want to spend and how serious you like your graphics (as well as what resolution you play), you want 1060, 1070, or 1080. "ti" suffix is better. Basically 1080ti > 1070ti = 1080 > 1070 > 1060
SSDs are the way and the light, but more specifically an m2 NVME one is stupidly fast. My m2 Samsung SSD is literally 6 times faster than my basic Samsung EVO SSD, and
I have the benchmarks to prove it.With a nice fast SSD (for boot and your most special games), add on a 4tb SATA drive and you're golden. (I have 1x m2 SSD, 1 x SSD, 1 x 4tb SATA, 1 x 1tb external SATA... covers all my needs)
Motherboards: Asus used to be the thing. I am now a bit averse to them, having had some issues. Personally, I steer toward MSI these days. YMMV.
RAM: Uh, it's kinda all the same anymore. Just pick something that has the right speeds. 16GB is the minimum now. 32GB is good.
Power supply: the usual suspects are still good: EVGA, Corsair, etc.
Cases: I'm stupidly fond of Coolermaster cases and will probably never build with any other brand ever again. They're just such a treat to work in and the craftsmanship is top notch every time.